In studies with probiotics, some of the probiotic strains of antibiotic-associated diarrhea development when used in combination with antibiotics it has been shown to be significantly reduced. Harvard / Yale probiotic Workshop Group, World Gastroenterology Organization in the prevention of antibiotic associated diarrhea probiotic strains showed that the level of evidence A1. However, probiotics effects are strain specific. Although Saccharomyces boulardii and Lactobacillus GG are well known strains for prevention of antibiotic associated diarrhea, knowledge about the Lactobacillus reuteri DSM 17938 is limited.